New crag, Edit crag basics

[salamca]

Update crag create and edit input dtos.

Multiple routes update mutation was mutating all routes in parallel which posed a problem with changing position for a bunch of routes. Updates are now processed seqeuentially and in order.

Added merge routes mutation. Although this could also be done through moveToSector mutation, another mutation probably makes things clearer. Also some unneeded input fields can now be omitted.

Added mutation for moving multiple routes to a sector. This could also be done with edit multiple routes mutation but then the moved routes would be positioned into another sector somewhat randomly (because position is sectorwise not cragwise). New mutation also takes care of this by always placing the moved routes at the end of the target sector.

test with plezanje-net/next-web#62